Means for and method of applying heat to ironing machines



June 17, 1947. w, GRANTHAM 2,422,481

MEANS FOR AND METHOD O APPLYING HEAT TO IRONING MACHINES Filed Aug. 12, 1943 Patented June 17, 1947 MEANS FOR AND METHOD OF APPLYING HEAT T IBONING MACHINES Frederick W. Grantham, Glencoe, 111. Application August 12, 1943, Serial No. 498,311

This invention relates to means for and method of applying heat to ironing machines.

The present method of ironing in commercial or industrial laundries consists of'bringing the work to be ironed into sliding contact with 'a steam heated ironing surface by a series of rolls.

The Work must be wet when ironed for proper tremendous increases in speed of ironing. By

employing the method of the present invention the increase in speed of present ironing machines is limited only by the mechanical limit of the machines themselves. convection heat are produced by a novel gas burner which can be installed in any existing ironing machine, and the machine need. not be specially designed.

The method consists in subjecting the work to be ironed to intense heat for a short period of time. The intense heat sterilizes the work, killing all disease germs, and the tim that the work is subjected to the heat is short enough that is is not scorched or otherwise impaired. By using this method of sterilizing instead of other methods a material increase in the life of the fabrics is effected. Chlorine and other sterilizing solutions have a detrimental effect. by impairing the strength of the fibers of fabrics and thereby shortening their life.

The burners employed with this method are of the refractorytype wherein premixed gas and airare directed onto the surface-of the refractory where it burns and brings the surface of the refractory up to incandescent temperature. Infra-red rays are emitted from this surface.

The separate burners are individually controllable so that various intensities of heat can be produced at different points along the ironing path; more heat is required at the start where the work is wettest, and less toward the end The radiant and 3 Claims. (01. 3856) cient to evaporate all moisture in the form of dry steam, or vapor. This eliminates the undesirable efl'ects of wet steam on the operators, and aids materially in speeding the drying.

Summarizing, the objects of the invention are: to sterilize the work being ironed; to increase the life of the fabrics; to increase the speed of present ironing machines with attendant savingsin labor, floor space and investment. Now, in order to acquaint those skilled in the art with the manner of constructing and employing my invention, reference may be had to the following detail description, taken in conjunction with the accompaning drawings, in

which:

Figure 1 is a plan view of the essential parts of an ironing machine showing the burners of the present invention in position;

Figure 2' is an end view of the same;

Figure 3 is an enlarged end view of a portion of the ironing machine and burners with, the work being ironed shown exaggerated;

Figures 4 and 5 are top and bottom views, respectively, of a portion of a burner; and

Figure 6 is an enlarged cross sectional view of the burner.

Referring now in detail to the drawings, the essential features of the ironing machine consist of a series of rolls l0 and an ironing surface II which forms the upper surface of a steam heated chest ii. The rolls H! are mounted in a suitable frame l4 and are rotated by suitable power means not shown here. -The steam chest i2 isan enclosed metal container into which steam is driven for heating the upper surface II. I

Towels I5 or other flat work, to be ironed are fed into the ironing machine over feeder belts Hi from which they enter the machine at I! over the ironing surface II and under the rolls I0 and emerge at l9, the rolls being rotated and the towels traveling in the direction indicated by the arrows. Tapes 20 are threaded under the rolls and over the ironing surface and towels and travel with the rolls to assure'that the towels are carried through the ironing machine and to prevent them from wrapping around the rolls.

The rolls are provided with padding 2| and are brought to bear against the towels and ironmg surface by spring pressure or other suitable means. The pressure of the rolls forces the towels to conform to th corrugations 22 throughout their travel through the machine by ,which action the towels are in firm and sliding contact with the ironing surface over all its area.

. 3 r Reference is made to towels, but it will be understood that any kind of flat work can be ironed,

whether towels, sheets, etc., and the fabrics being ironed are referred to herein as wor burners generate both infra-red rays (radiant heat) and convection heat. The burners operate on a premix principle, 1. e., air and gas are mixed to proper combustion proportions and de-, livered under pressure to the manifold 25 from which the mixture is forced-through jets 26 and onto the surface 21 of refractory 2-9. ,The burning of the gas on the surface of the refractory brings the surface up to incandescent temperature (about 2500) from which infra-red rays or radiant heat is emitted. There is in addition convection heat generated as in an ordinary gas burner. the manifold for shutting off separate jets so that the total capacity of the burners can be cut down. Figures 4and 5 show how a burner appears, showing a series of jets and shut-oils.

With all the jets open the entire length of the channel 3! becomes radiant. A great advantage of this feature is that there is even distribution of heat along-the burner, and entire elimination of "sptted or bunched heat.

However, with individual shut-offs provided for the separate Jets, the radiant portions can be spaced alongthe length of the burner, if dewidth of the ironer when narrow work is being ironed. a The novel construction and design of the burner render it exceedingly eifective in drying in an ironera very compact device capable of generating a great amount of heat in a smallspace.

The gas and air mixture is developed by a sure regulator H are employed .in the gas line 42 for controlling the flow of gas. Preferably, the motor'36 is hooked in with the power unit of the ironing machine so that the burners will turn on and ofi with the ironing machine. Pilots 44 automatically light the burners when the ironing machine starts up. i

The mixture of gas and air on leaving the blower 35 passes through the line 45 to the header 4G and the separate burners 24. Turn-down valves 49 and 50 are placed in the header 46 to control the amount of flow to the burners 24c and 24d. The towels pass through the machine in the direction indicated by the arrow i. At the entrance of the machine the burners 24a and 24b can be turned on full force'without dam- ,age tothe towels or rolls, for at this point the towels are the wettest and will take more .heat. As the'towels travel along they become drier Individual shut-ofls 30 extend through v a 4. I and consequently the amount of heat applied to them must be less. Turn-down valves 49 and It can be individually regulated for cutting down the capacity of the burners 24c and'24d. An advantageous feature of this novel burner is that they are adapted to a wide range in turn-down, and accurate control; This arrangement therefore allows progressively decreasing the heat as the work being ironed becomes drier. In additionto this control, shut-offs canbe operated to regulate the total capacity or my burner. This regulation controls both the amount of infra-red rays and convection heat.

As shown in Figure 3 the burner l5.- The paths of the infra-red rays are indicated by the lines 52 (see also Fig. 6). The height of the burners above the towels determines the intensity of the infra-red-rays applied to the towels. The surface of the refractory 24 reaches a temperature of 2500 F., and at a short distance of several inches from this surface'the towels are exposed to a ,temperatureof about 1000 F. This intense heat has a quick drying effect, and the towels are subjected to it for only sired, for directing heat in only a portion of the" The width of the burners is such as to almost fill the space between the rolls. The burners then act to confine the convection heat at the surface of the towels. Convection heat, which is also generated by. the burner,'is also effective in drying the work.

With this method of drying, speeds of production never before heard of have been attained. Ironers are operated at theirmaximum mechanical limits with the burners. operating at far below their limit. The advantages and savings are too apparent to need elaboration, such as saving in floor space, more production for investment, and tremendous savings in labor.

Another and just as important advantage lies in the sterilizing efiect produced by this method of drying. Intense heat will kill disease germs long before it will injure the fabric of the work being ironed. The length of time that the work is subjected to the heat is sufiicient that all disease germs will be killed. The prevailing methods of sterilizing employ chlorine and other solutions. Chlorine damages the fibers of the fabrics and shortens their life, and the loss by such procedure reaches great proportions in large.

establishments. I The method of the present invention overcomes this great loss.

While I have set forth'above a particular passes through the ironer, and emerges dry, which comprises directing infra-red rays onto the work being ironed to a relatively great extent at the en-' trance of the ironer where the work enters wet and the moisture content'is greatest, and to a progressively lesser extent at successive points along the ironer so that the work is subjected to progressively less lieat as it passes through the ironer and the moisture content of the work decreases. i

24 is inverted and placed in between adjacent rolls l0 so that the infra-red rays are directed onto the towels .of applying heat to work being. ironed in an-ironer in which the work enters wet,

rolls and an ironing surface and in which thework being ironed-passess successively between the rolls and ironing surface, the work being dried as it passes through the ironer, comprising burners positioned between adjacent rolls. the burners generating heat and being arranged so as to direct the heat onto the work being ironed as it passes from one roll to another and means controlling individual burners in such manner as to regulate the. amount of heat applied to the work in proportion to the amount of moisture retained in the work along its path through the ironer.

3. The method of applying heat to work being ironed in an ironer in which wet, passes through the ironer, and emerges dry, which comprises directing heat downwardly onto and confining it above the surface of the work being ironed to a relatively great extent at the entrance of the ironer where the work enters wet and the moisture content thereof is great est, and to a progressively lesser extent at sucthe work enters cess'ive points along the ironer so that the work is subjected to progressively less heat as it passes through the ironer and the moisture content of the work decreases.

F.W. GRANTHAM.

REFERENCES CITED The following references are of record in the o file of this patent:

UNITED STATES PATENTS Number Name Date 1,936,027 Pointon Nov. 21, 1933 1,171,970 Mertens Feb. 15, 1916 1,270,153 Heidler June 18, 1918 2,355,391 Nelson et a]. Aug. 8, 1944 2,127,956 Helmer Aug. 23, 1938 2,268,988 Hess et al. Jan. 6, 1942 2,313,173 Schneider et al. Mar. 9, 1943 FOREIGN PATENTS Number Country Date 678,528 Germany July 17, 1939 507,223 Germany Sept. 15, 1930 

